Presumptive Republican presidential nominee John McCain travels to Colombia to discuss one of his big differences with Barack Obama –- foreign trade policy. Dana Bash has the story on the Arizona senator’s support for free trade.

Also: In the race for the White House, Sens. Barack Obama and John McCain are locked in a virtual dead heat. Senior Political Correspondent Candy Crowley discusses the latest CNN/Opinion Research Corporation poll.

In Obama's first comments about his widely-covered phone conversation with the former president Monday morning, the Illinois senator said the two did not dwell on the prolonged and at times divisive primary race.

"We did not belabor the primary season,” Obama told reporters Tuesday. “I think what we both acknowledged is, is that when you’re in a tough primary battle you say things that afterward you may end up thinking, that may have been a little intemperate. But that’s the nature of political campaigns.”

Obama also said he wants Clinton to become a staple on the campaign trail next fall, even though the former president's periodic outbursts and at-times aggressive promotion of his wife's candidacy drew widespread criticisms.

“I absolutely want Bill Clinton campaigning for me,” Obama said, adding, "He is one of the most gifted public officials of our generation and has been one of the most successful presidents that we’ve had in my lifetime."

The high-profile conversation came more than two weeks after Hillary Clinton formally abandoned her own White House bid and amid rumors the 42nd president holds a grudge against the man who knocked his wife out of contention for the party's presidential nomination. Some reports have said Clinton is specifically upset with Obama's criticisms of his administration over the course of the campaign and the media's coverage of the race.

In an interview on CNN Sunday, close Clinton friend and former Democratic National Committee Chairman Terry McAuliffe denied the reports that the former president is angry with Obama, calling that notion "ridiculous."

(CNN) - Former Secretary of State Colin Powell, who remains a popular figure among Democrats and Republicans, recently sat down with both presidential candidates, CNN has confirmed.

The Hotline first reported the meeting earlier Tuesday.

According to an associate of Powell, the former Bush administration member and onetime chairman of the Joint Chiefs of Staff had "pleasant, private conversations" recently with both Sens. Barack Obama and John McCain. An Obama campaign source confirms the Illinois senator recently met with Powell. McCain's campaign has not returned a request for comment.

(CNN) - With the dust having finally settled after the prolonged Democratic presidential primary, a new CNN/Opinion Research Corporation poll shows Sens. John McCain and Barack Obama locked in a statistical dead heat in the race for the White House.

With just over four months remaining until voters weigh in at the polls, the new survey out Tuesday indicates Obama holds a narrow 5-point advantage among registered voters nationwide over the Arizona senator, 50 percent to 45 percent. That represents little change from a similar poll one month ago, when the presumptive Democratic presidential nominee held a 46-43 percent edge over McCain.

CNN Polling Director Keating Holland notes Tuesday's survey confirms what a string of national polls released this month have shown: Obama holds a slight advantage over McCain, though not a big enough one to constitute a statistical lead.

"Every standard telephone poll taken in June has shown Obama ahead of McCain, with nearly all of them showing Obama's margin somewhere between three and six points," Holland said. "In most of them, that margin is not enough to give him a lead in a statistical sense, but it appears that June has been a good month for Obama."

But the new CNN/ORC polls shows the race gets even tighter when the two most prominent third-party presidential candidates are considered. In a four way match-up that includes independent candidate Ralph Nader and Libertarian candidate Bob Barr, Obama's lead over McCain dwindles to 3 percentage points, 46 percent to 43 percent. (Nader registers 6 percent while Barr gets 3 percent.)

But it remains unclear just how much effect Nader and Barr will have on the election, as summertime surveys often overstate the eventual Election Day showing of third-party candidates.

"A useful rule of thumb is that third-party candidates in November get no more than half the support polls show them having in June or July," Holland said.

Meanwhile, one day after the Illinois senator sharply defended his devotion to America during a high-profile speech in the crucial swing state of Missouri, the new survey shows some voters continue to have lingering questions about his patriotism.

(CNN) - Retired Gen. Wesley Clark, appearing on CNN's "The Situation Room" Tuesday, continued to press the argument that John McCain is not suited to be commander-in-chief, and took aim at the Arizona senator's "judgment."

"I've never said anything to dishonor John McCain … I like him. But I will say this, that when it comes to being President of the United States, it's about judgment," Clark told CNN's John Roberts. "And I've seen stronger judgment from Barack Obama, despite the fact that he doesn't have military experience than I've seen from John McCain despite all his worldly travels.

"To me, this is about, and I hope the American people will make the decision based on judgment," he added.

Clark also criticized Orson Swindle, a McCain surrogate and former Vietnam POW, who blasted Clark's record as Supreme Allied Commander of NATO.

"I don't know Orson. I'm sure he's an outstanding man and did a great job in uniform. He doesn't know me either," said Clark.

"But I did in my last command as the head of the forces in NATO, lead the forces of NATO in the fight to stop ethnic cleansing in the Balkans. We did win a war. We bombed for 78 days … we did it without the loss of a single American soldier … We did it with a combination of diplomacy and force," he said.

Clark also discussed his support in 2004 for John Kerry, namely on his military experience, and how it differs from McCain's.

"John McCain basically served honorably while in uniform, he did everything the country could have asked," Clark told CNN. "What John Kerry did is John Kerry got out of the uniform and took a judgment, a judgment I didn't agree with at the time, but he had the moral courage to stand up for himself and oppose the conflict in Vietnam.”

ZANESVILLE, Ohio (CNN) – Barack Obama said Tuesday that he has not spoken with Gen. Wesley Clark regarding his controversial comments on John McCain's military service - and that a conversation with him is "not a priority" because he doesn't think the remarks are something voters are worried about.

"I'm happy to have all sorts of conversations about how we deal with Iraq and what happens with Iran," the presumptive Democratic nominee told reporters at a press conference in Zanesville, Ohio.

"But the fact that somebody on a cable show or on a news show like Gen. Clark said something that was inartful about Sen. McCain I don’t think is probably the thing that is keeping Ohioans up at night."

The Illinois senator refused to say whether or not he thinks Clark owes McCain, the presumptive Republican nominee, an apology.

Obama also said that his comment yesterday that "no one should ever devalue" military service, including "supporters of both sides" was not a response to Clark.

"I think my staff will confirm that that was in a draft of that speech that I had written two months ago," he said.

McCain tours the Worth and Company factory in Pipersville, Pennsylvania, Monday.

(CNN) - As John McCain prepares to promote the advantages of free trade during a high-profile trip to Colombia and Mexico, a poll released Tuesday suggests the issue may pose a political hurdle for the Arizona senator as the general election campaign heats up.

According to the CNN/Opinion Research Corporation poll, 51 percent of the Americans questioned view foreign trade as a threat to the economy - the first time in a CNN poll that a majority of respondents report holding negative views on free trade.

That compares to only 35 percent of those asked who felt that free trade posed a threat to the economy in 2000, and 48 percent who felt it was a threat in 2006.

Now only four in 10 the Americans questioned say free trade presents an opportunity for economic growth, a sentiment that clearly makes the issue a challenge for McCain, especially in the crucial Rust Belt states most affected by the loss of manufacturing jobs over the last decade.

"It's possible that John McCain's decision to highlight his free-trade position may wind up losing him some votes among Americans who feel threatened economically by competition from other countries," CNN Polling Director Keating Holland said. "Recent polls in states like Pennsylvania and Michigan have shown McCain well behind Barack Obama. Calling attention to his stand on an issue like trade may be a part of the problems he apparently faces in those Midwestern states."

(CNN) - As John McCain’s campaign continued to characterize a Sunday comment by former Gen. Wesley Clark as an attack on the former Navy pilot’s military service, a McCain surrogate countered Tuesday by criticizing Clark’s record as Supreme Allied Commander of NATO.

Orson Swindle, who was a prisoner of war with McCain in Vietnam, told reporters on a campaign conference call Tuesday that the high-ranking former military officials who back the presumptive Republican nominee might not hold Clark in high regard.

"General Clark probably wouldn't get that much praise from this group,” said Swindle. “I can't speak for them, but we all know that General Clark, as high-ranking as he is, his record in his last command I think was somewhat less than stellar."

Clark’s last active duty position was at the helm of NATO from 1997-2000, during which he commanded joint military activity in the Kosovo conflict.

Mayor Rudy Giuliani, former presidential candidate turned McCain supporter, will be a guest today in “The Situation Room” and you can be a part of the interview. Does Mayor Giuliani agree with Sen. Lieberman that the next president will be tested early by a terrorist attack? Why does he think Sen. McCain will be a better president than Sen. Obama?

Send us your questions for Mayor Giuliani on video, and be sure to keep them clear and concise. Your videos could be used on air - and your views a part of the best political team on TV.